Gripper mechanism



May 24, 1966 w. DE FRANK 3,252,727

GRIPPER MECHANISM Filed Nov. 13, 1963 FIG.3

FIG.2

INVENTOR.

WILLIAM DE FRANK li wn ATTORNEYS United States Patent 3,252,727 GRIPPER MECHANISM William De Frank, 34 Windsor St., Rochester, N.Y. Filed Nov. 13, 1963, Ser. No. 323,471 11 Claims. (Cl. 294-2(l) This invention relates generally to gripping devices and more particularly to gripping devices for installing and removing tubular fluorescent light bulbs from light fixtures.

It has long been a problem to install and remove fluorescent light bulbs from light fixtures without great inconvenience. Many fluorescent light fixtures constitute an integral part of a suspended ceiling or are otherwise mounted at the ceiling at such a height as to require a step ladder or other facilitis such as stepping on a chair, etc., for the removal of the light bulb. In order to overcome this problem, other devices have been improvised to grip the fluorescent light bulbs for removal from the fixture. Many of these devices are unsatisfactory or are only partially satisfactory or are not practical for commercial manufacture. My invention presents a novel solution to this problem, and generally provides a novel gripping device, with improved safety.

It is one object of my invention to provide improved gripping apparatus generally.

It is a specific object of my invention to provide an improved apparatus for installing and removing tubular fluorescent light bulbs from light fixtures and particularly such light bulbs which must be moved axially in opposi tion to spring pressure in the fixture for removal and replacement of the light bulb.

Other objects and advantages of this invention will be particularly set forth in the claims and will be apparent from the following description, when taken in connection with the accompanying drawings, in which:

FIG. 1 is a side elevational view of one embodiment of my invention with parts broken away and partly in section to illustrate details of the construction;

FIG. 2 is an enlarged sectional view taken along the line 22 of FIG. 1 looking in the direction indicated by the arrows, and

FIG. 3 is an enlarged fragmentary top planar view of the embodiment illustrated in FIG. 1.

With reference to the figures, I have illustrated an elongated tubular handle broken away as indicated by the arrow 11; it will be understood that the tubular handle 10 is elongated and of selected length corresponding to the height at which a fluorescent tubular light bulb or element, shown in broken line at 12, is located with respect to the operator of my device. Light bulb or element 12 has contact pins 13 at opposite ends thereof. At the bottom end of tubular handle 10 is a knurled handpiece 14 which the operator'holds.

The upper end of handle 10 receives internally thereof a threaded bolt 16 which has a circular head 17, the outside diameter of which is substantially the same as the internal diameter of the tubular handle 10 for axial alignment thereof. Bolt 16 is rigidly mounted interiorly of the handle 10 by a double-headed rivet 18 passing through a bore through the handle 10 and a bore through the shank of the bolt 16.

Bolt 16 has threads 20 at its upper end receiving a threaded nut 22 (FIG. 2) having a pair of laterally ex tending studs 24 extending transversely of the axis of the light bulb or element 12. Studs 24 pivotally carry a pair of laterally extending horizontal channel arms 26 and 28, generally of V shaped cross section. Arms 26 and 28 have resilient (preferably rubber or plastic) light bulb engaging tips 30 and 32 mounted on opposite free ends respectively of the pair of arms and adapted to engage the lower surface of light bulb 12.

Intermediate the pivotal connection at studs 24 and the opposite free ends on which the resilient tips 30 and 32 are mounted, I provide gripper means or elements generally indicated by numerals 34 and 36 each having rigid inner structures 35 and 37 respectively, preferably of steel or cast iron and formed in substantially a C configuration as shown in FIG. 2, both of which are adapted to partially embrace the tubular fluorescent light bulb 12. Gripper elements generally indicated by numerals 34 and 36 are rigidly or fixed or stationary mounted to the substantially V shaped cross-sectional arms 26 and 28 as illustrated in FIG. 2 by welding 38. Gripper elements 34 and 36 include a resilient casing 39 and 40 received on the rigid C frames 35 and 37 respectively. The resilient gripper coverings 39 and 40 have a cutaway portion 42 as illustrated in FIG. 2 and FIG. 3 in order to present a readily slidable surface intermediate my device and the light fixture in which tubular fluorescent lights are mounted, thereby preventing any frictional binding which might otherwise occur if the light fixture is constructed to receive the light bulbs 12 in close proximity of the fixture.

A flared collar 44 (illustrated of plastic composition) has a lower internal diameter or bore 46 receiving the upper end of tubular handle 10 which abuts an internal shouldered portion 48 formed at the upper end of bore 46. This construction permits relative rotation between the handle 10 and the flared collar 44 while maintaining the collar 44 on the upper end of the handle 10. An upper flared portion 50 of collar 44 has internal substantially axial-ly extending flutes or grooves 52 in which the vertex of the V formed in arms 26 and 28 are received for the purpose herein-after described.

As mentioned above, my invention is particularly suitable for use with the variety of tubular fluorescent light bulbs axially inserted into the light fixture sockets 54 and 56 by axial movement of the bulbs 12 in opposition to a compression spring 58 mounted in an internal bore 60 in the right-hand end socket 56 of the light fixture.

In an open position (not shown) the threaded portion 20 of the bolt 16 has been threaded downwardly, by rotation of the handle 10 relative to the arm 26 and 28, until the nut 22 is substantially at the top of the threads 20. In the open position, the ends of the arms 26 and 28 pivoted to studs 24 are elevated on the bolt 16 and the arms are disposed along a more nearly horizontal axis than illustrated in FIG. 1. In a closed or gripping position illustrated in FIG. 1, it will be noted that the arms 26 and 28 are disposed at an upwardly inclined angle to the horizontal axis. In the open position (not shown), the light bulb 12 is readily received between the C shaped gripper elements 34 and 36 at the upper surface of the bulb 12 and the resilient tips 30 and 32 at the lower surface of the bulb 12.

In order to apply gripping force to the free bulb removed from the light fixture, the operator simply places the bulb 12 between the gripper element 34 and 36 on the top and resilient tips 36 and 32 on the bottom and thereafter either holds the flared collar 44 or one arm 26 or 28 secure with one hand while he rotates the handle 10 with the other hand in a clockwise direction as viewed from the lower end of handle 10. In this manner the nut 22 is threaded downwardly on the threads 20 of the bolt 16 to pivot free ends of the arms 26 and 28 upwardly, to the gripping or closed position shown in FIG. 1, thereby applying gripping pressure at the C shaped gripper elements 34 and 36 to the upper surface at A and at the resilient tips 30 and 32 to the lower surface at B.

As gripping force is transmitted to the bulb, the vertex of the V shaped arms 26 and 28 are seated in the flutes or grooves 52 to prevent rotation of the collar 44 relative to the arms 26 and 28. However, it will be understood that the collar 44 could be rigidly mounted at the upper end of the handle without flute 52 so that as locking force is applied there is frictional rotation between the upper end of the flared portion 50 of the collar 44 and the arms 26 and 28 instead of between the collar 44 and handle 10 as is illustrated in the drawings.

After the bulb 12 is secure within my gripper device described above, the operator in the usual manner inserts right hand contact pin 13 into bore 60 of socket 56 in opposition to spring 58 as indicated by the arrow 61 a sutlicient distance to permit the left hand contact pin 13 to slip into socket 54. After the bulb 12 is inserted in the fixture, the handle 10 is rotated in the opposite direction threading the nut 22 downwardly on the bolt threads 20, thereby releasing the gripping elements from the bulb. It will be understood that this arrangement permits remote control of the gripping device by rotation of elongated handle 10.

The operator simply reverses the above described steps in order to remove the bulb.

The cut-away 42 in the resilient covering 39 eliminates the possibility of friction between the light fixture and gripper elements 34 and 36 which might otherwise prevent axial movement to the right when the bulb is being removed.

To someone skilled in the art it will be understood that it is not necessary that both of the arms 26 and 28 pivot, but that locking force could be fulfilled if one of the arms is mounted rigidly with respect to the handpiece 10. It is necessary to provide pivotal action of only one of the arms 26 or 28 thereby to move my device into locking-gripping relationship with the bulb or element 12 in the position illustrated in FIG. 1. However, I have illustrated the preferred arrangement.

While I have shown and described the preferred form of mechanism of my invention it will be apparent that various modifications and changes may be made therein, particularly in the form and relation of parts, without departing from the spirit of my invention as set forth in the appended claims.

I claim:

1. A gripping device for gripping a substantially axially extending element comprising: a pair of arms; means for pivoting one end of at least one of aid arms relative to the other of said arms; gripper means carried intermediate opposing free ends of the arms; said gripper means being constructed to partially surround and embrace said element when said element overlies said arms; said gripper means being coactive with said opposing free ends of the arms to lock said element into pressure locking relationship responsive to pivoting force of said pivoting means.

2. A gripping device in accordance With claim 1 in which said pivoting means includes a handle, and threaded means between said handle and said pivotal arm applying gripping force through said pivotal armand gripper means to said element.

3. A gripping device for gripping a substantially axially extending element comprising: a pair of arms pivotally interconnected at substantially adjacent ends thereof; at least one of said arms having at least a pair of gripper portions constructed to apply opposing forces to said element at axially spaced position along said element the other of said arms having gripper means comprising at least a free end thereof, said free end being axially spaced on the opposite side of said pivotal interconnection from said gripper portions; and means for pivoting at least one of said arms relative to the other of said arms, whereby said gripper portions of said one arm and said gripper means are moved into pressure gripping relationship at points axially spaced of said element.

4. A gripping device for gripping a substantially axially extending element comprising: a pair of arms; each of .said arms having at least a pair of gripper portions constructed to apply opposing forces to said element at axially spaced points along each arm; means pivotally interconnecting said arms at substantially adjacent ends thereof for pivoting said arms relative to each other and one pair of gripper portions being disposed axially on one side of said interconnection and the other of said pair of gripper portions being axially disposed on the opposite side of said interconnection whereby all of said gripper portion are moved into pressure gripping relationship at points axially spaced of said element.

5. A gripping device for gripping a substantially axially extending element comprising a pair of arms, each of said arms having a gripper portion intermediate the ends of the arms constructed to partially surround and embrace said element when said element overlies said arms and means at one end of each of said arms for pivoting at least one of said arms relative to the other whereby said gripper portions and opposing free ends of said arms are lockable into pressure gripping relationship at four points axially spaced of said element.

6. A gripping device in accordance with claim 5 in which said pivoting means includes a handle and threaded means between said handle and said pivotal arm for applying gripping force through said arms and gripper means to said element.

7. A gripping device for gripping a substantially axially extending element comprising: a pair of arms; each of said arms having a gripper portion intermediate the ends of the arm constructed to partially surround and embrace said element when said element overlies said arms; a handle having a hollow end adapted to receive one end of each of said arms and a threaded connection between said one end of each of said arms and said handle within said hollow end whereby said gripper portions and opposing free ends of said arms are movable into pressure gripping relationship at four points axially spaced of said element.

8. A gripping device for gripping a fluorescent light bulb comprising a pair of arms; resilient means for pivoting one end of at least one of said arms relative to the other of said arms; gripper means carried intermediate opposing free ends of the arms; said gripper means being constructed to partially surround and embrace said element when said element overlies said arms, said arms carrying resilient grippers at opposing free ends thereof; said gripper means being coactive with said opposing free ends of the arms to lock said element into pressure locking relationship responsive to pivoting force of said pivoting means.

9. A gripping device for gripping a fluorescent light bulb comprising a pair of arms; resilient means for pivoting at least one of said arms relative to the other; each of said arms having a gripper portion intermediate the ends of the arm constructed to partially surround and embrace said element when said element overlies said arms; said arms carrying resilient grippers at opposing free ends thereof; a handle having a hollow end adapted to receive one end of each of said arms and a threaded connection between said one end of each of said arms and said handle within said hollow end whereby said gripper portions and opposing free ends of said arms are movable into pressure gripping relationship at four points axially spaced of said elements.

10. A gripping device for gripping a substantially axially extending element comprising: a pair of arms interconnected at substantially adjacent ends thereof; at least one of said arms having at least a pair of tationary gripper portions constructed to apply opposing forces to said element at axially spaced positions along said element; the other of said arms having gripper means comprising at least a free end thereof, said free end being axially spaced on the opposite side of said interconnection from said gripper portions and means for moving at least one of said arms relative to the other of said arms, whereby said gripper portions and gripper means are moved into pressure gripping relationship at points axially spaced of said element.

11. A gripping device for gripping a substantially axially extending element comprising: a pair of arms; each of said arms having at least a pair of gripper portions constructed to apply opposing forces to said element at axially spaced positions along said element; and means for pivoting at least one of said arms relative to the other of said arms about an axis extending transversely of said axially extending element and lying in a plane parallel to said element, whereby all of said gripper portions are moved into pressure gripping relationship at points axially spaced of said element.

References Cited by the Examiner UNITED STATES PATENTS 1,817,233 8/1931 Burngardner 29492 2,392,865 1/ 1946 Smith 29420 2,658,786 11/1953 Ziese 2942O 10 GERALD M. FORLENZA, Primary Examiner.

SAMUEL F. COLEMAN, Examiner 

1. A GRIPPING DEVICE FOR GRIPPING SUBSTANTIALLY AXIALLY EXTENDING ELEMENT COMPRISING: A PAIR OF ARMS; MEANS FOR PIVOTING ONE END OF AT LEAST ONE OF SAID ARMS RELATIVE TO THE OTHER OF SAID ARMS; GRIPPER MEANS CARRIED INTERMEDIATE OPPOSING FREE ENDS OF THE ARMS; SAID GRIPPER MEANS BEING CONSTRUCTED TO PARTIALLY SURROUND AND EMBRACE SAID ELEMENT WHEN SAID ELEMENT OVERLIES SAID ARMS; SAID GRIPPER MEANS BEING COACTIVE WITH SAID OPPOSING FREE ENDS OF THE ARMS TO LOCK SAID ELEMENT INTO PRESSURE LOCKING RELATIONSHIP RESPONSIVE TO PIVOTING FORCE OF SAID PIVOTING MEANS. 